Steam-trap.



W. G. DODD.

STEAM TRAP.

APPLIOATION FILED DEO.17, 1912.

Patented June 16,1914.

InvenTur Wfinessex COLUMBIA PLANOOIAPH CO VIAIMIND'IOPL D. c.

WILLIS G. DODD, OF SAN FRANCISCO, CALIFORNIA.

STEAM-TRAP.

Specification of Letters Patent.

Patented June 16, 1914.

Application filed December 17, 1912. Serial No. 737,237.

To all whom it may concern Be it known that I, WVILLIs G. Donn, a-

citizen of the United States, residing within the city and county of San Francisco, State of California, have invented certain new;

and useful Improvements in Steam-Traps, whereof the following is a specification.

My invention relates to steam traps adapted to automatically draw off the con densation from any system of piping in,

which steam is conveyed or employed, and belongs to that class known as expansion traps, depending for their operation upon the difference in the co-eflicient of expansion between two different metals, one of these metals carrying a valve seat and the other carrying a valve, which cooperate with each other to open and close the valve, when subjected to varying degrees of temperature, thus permitting the ejection of any condensation which may have collected.

My improvement however, pertains more particularly to the self contained type of these expansion traps, in which one of the expansion members incloses the other. Heretofore traps of this type have been constructed by inclosing a brass expansion tube, within an iron tube, which necessarily leaves a space between the two tubes, and I have discovered that a trap constructed upon this principle cannot operate against a head or pressure, without the escape of live steam, as the discharged condensation from the expansion tube backs up into and fills the space between the two tubes substantially destroying the operation of the expansion tube and practically converts the trap into a condenser.

The object of my invention is to overcome this defect, by so constructing a trap of this type that it will operate against a head or pressure and deliver the condensation discharged without the loss of live steam, to a tank or other receptacle located, as for example, above the feed pump or boiler from whence it came.

A further object of the invention is to so construct a trap of this type in such a manner that, by minor changes or substitution of parts, the capacity of the trap may be greatly increased or diminished as conditions of operation may require, a feature of importance in, the cheapening of manufacture and greatly increasing the range of the utility of the device.

How I attain these objectsin a trap of this type is illustrated in the accompanying drawing, described in the following specification and pointed out in the claims.

Similar letters or numerals refer to similar parts.

The drawing, broken away in the center, is a sectional elevation of the device.

Referring to the letters of reference: B is a sleeve coupling, having an inlet at C through which steam and condensation enters the trap.

D is a boss, formed integral with the sleeve coupling by means of the ribs E.

To the outlet end of the sleeve coupling an expansion tube G preferably of brass, is

secured, and to the opposite end of this tube a valve seat H is secured. An iron rod J passes loosely through the valve seat H, the

which is engaged by the auxiliary valve M which has a screw thread relation with the rod J, and preferably forms a ball and socket joint with the main valve K and aids in properly adjusting it to the main valve seat H. v

The casing N attached to the valve seat, may be made of any desired shape or design as it possesses no function other than to re ceive the discharged condensation from the trap and guide it through the opening or outlet pipe P, which conducts it to a tank usually located above the feed pumps or boiler from whence it came.

T is a stem for the auxiliary valve M preferably formed integral therewith by means of which the valve is operated The operation is as follows: The auxiliary valve M is unscrewed sufficient to permit the main valve K to move away from the valve seat H, steam is then admitted through the inlet C and passes through the tube G, until the tube is thoroughly heated and fully expanded. The auxiliary valve M is then screwed up until the main Valve K is fairly seated and the tube sealed. Any condensation in the system will now begin to collect in the expansion tube, and when a sufficient quantity has collected to cool the tube, it will contract, and pull the seat away from or loosen the main valve K thus permitting the steam pressure to force the condensation out of the expansion tube and keep it from again its seat due to the difference in the co-efiicient of expansion between the iron rod and the expansion tub-e. This distance between the valve and valve seat under constant pressure or temperature, remains constant, therefore if it is desirable for any reason that the capacity of the trap be enlarged or decreased, a larger or smaller diameter of valve seat may be substituted for the accomplishment of this purpose, and it will be observed that the trap is designed and constructed to accomplish this result, and at a trifling expense.

Having thus described my invention, I claim,

In a steam trap of the class described, comprising an inlet coupling to which are rigidly attached an outer expansible mem ber and an inner non-expansible member, a main valve seat attached to the discharge end of the expansible member, a main valve loosely journaled upon the non-expansible member and adapted to engage the main valve seat, an auxiliary valve seat centrally located within said main valve, an auxiliary valve adapted to engage said auxiliary valve seat by means of an adjustable relation with the non-expansible member, as and for the purpose set forth.

2. In a steam trap of the class described, comprising an inlet coupling to which are rigidly attached an outer expansible mem-. ber and an inner non-expansible member, a:

main valve seat attached to the discharge end of the expansible member, a main valve loosely journaled upon the non-expansible member and adapted to engage the main valve seat, an auxiliary valve seat centrally located within said main valve, an auxiliary valve adapted to engage said auxiliary valve seat by means of an adjustable relation with the non-expansible member in combination with a detachable valve casing formed with a plurality of openings through one of which means are introduced for operating the auxiliary valve as and for the purpose specified.

3. In a steam trap, the combination of a valve casing formed with a plurality of openings two of which are in alinement with each other, a removable valve seat and a guiding member detachably secured into said alining openings, an expansible conduit secured to and communicating with the valve seat, a non-expansible member extending longitudinally of and within the expansible conduit and valve seat, one end of said member being operatively connected to the expansible member, the other end being free and extending beyond the valve seat, a rod guided by said guide member and adjustably secured to the free end of the non-expansible member, and a valve loosely surrounding said non-expansible member and supported by said rod, said valve and said rod having cooperating concave and convex surfaces, whereby the valve may have a rocking movement and thereby adjust itself with respect to the valve seat.

In testimony that I claim the foregoing I have set my hand this 11th day of Dec. 1912, in the presence of witnesses.

W. G. DODD.

Vitnesses:

W. F. DURAND, A. M. SEWELOH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. O. 

